Detalles de publicación

PP 017077

The Magellanic Inter-Cloud Project (MAGIC) III: First spectroscopic evidence of a dwarf stripping a dwarf

Ricardo Carrera (1,2), Blair C. Conn (3), Noelia E. D. Noël (4), Justin I. Read (4), Ángel R López Sánchez (5,6)
(1) Instituto de Astrofísica de Canarias, Spain, (2) Departamento de Astrofísica, Universidad de La Laguna, Spain, (3) Research School of Astronomy and Astrophysics, Mount Stromlo Observatory, Australia, (4) Department of Physics, University of Surrey, UK, (5) Australian Astronomical Observatory, Australia, (6) Department of Physics and Astronomy, Macquarie University, Australia
The Magellanic Bridge (MB) is a gaseous stream that links the Large (LMC) and Small (SMC) Magellanic Clouds. Current simulations suggest that the MB forms from a recent interaction between the Clouds. In this scenario, the MB should also have an associated stellar bridge formed by stars tidally stripped from the SMC by the LMC. There are several observational evidences for these stripped stars, from the presence of intermediate age populations in the MB and carbon stars, to the recent observation of an over-density of RR Lyrae stars offset from the MB. However, spectroscopic confirmation of stripped stars in the MB remains lacking. In this paper, we use medium resolution spectra to derive the radial velocities and metallicities of stars in two fields along the MB. We show from both their chemistry and kinematics that the bulk of these stars must have been tidally stripped from the SMC. This is the first spectroscopic evidence for a dwarf galaxy being tidally stripped by a larger dwarf.

 
Aceptado para publicación en MNRAS | Enviado el 2017-07-27 | Proyecto 301204